The present invention relates generally to hinges, and more particularly to a tamper resistant hinge assembly and to locks employing a tamper resistant hinge assembly.
A hinge commonly employs a hinge plate and a pivot arm held together by a pin around which the hinge plate and pivot arm can rotate with respect to one another. The hinge plate is typically fixed by fastening it to, for example, a fixed object such as a wall or a door frame in a wall, usually attached to the frame using screws or bolts through mounting holes formed in the hinge plate. The pivot arm is attached to a moveable object such as a door. The pivot arm pivots around the pin thus allowing the door or other moveable object to pivot with respect to the fixed object. In many applications, more than one hinge is provided between the fixed object and the moveable object.
In some applications, the hinges are arranged so that the pivot arm overlaps the hinge plate when the door is in the closed position. An example of such a hinge arrangement is found in a bar lock configuration for trailer doors.
In some situations, it is desired to control access to the space behind a door, and lock mechanism may be provided to control access to the space behind the door. In some applications, one or both of the hinge plate and the pivot arm are fastened to the face of the frame and the door and are thus exposed when the door is in a closed position. This provides an opportunity to defeat the lock mechanism by removing the fasteners that attach one of the hinge plate and the pivot arm to either the door or the frame.